The McNair Scholars Research JournalCopyright (c) 2017 University of Nebraska - Lincoln All rights reserved.http://digitalcommons.unl.edu/mcnairjournal
Recent documents in The McNair Scholars Research Journalen-usSat, 14 Jan 2017 05:17:11 PST3600Investigating Antibiotic Resistance Levels of <i>Salmonella</i> Internalized in Lettuce Leaveshttp://digitalcommons.unl.edu/mcnairjournal/9
http://digitalcommons.unl.edu/mcnairjournal/9Fri, 16 May 2014 10:23:01 PDT
Contamination of food crops by the human pathogen Salmonella is a food safety threat worldwide. Though using treated wastewater for irrigation is a sustainable practice, it may introduce trace levels of Salmonella that may contaminate food crops. Salmonella could develop resistance to antibiotics present in wastewater. The overall goal of the project is to increase the understanding of the public health risk associated with the use of treated wastewater to irrigate food crops. The objective of this particular study is to determine the antibiotic resistance level of Salmonella internalized in lettuce leaves. In this experiment, thirty-six plants of the lettuce (Lactuca sativa) cultivar Green Salad Bowl were grown hydroponically in Hoagland growth medium and harvested at 21, 35, and 48 days. Five days before each harvest, solutions containing the antibiotic oxytetracycline (OTC) and the bacteria Salmonella enterica serovar Infantis were added to the hydroponic growth medium. At each harvest time, bacteria extracted from the lettuce leaves were quantified on XLD agar plates amended with 1, 2, 4, 8, 16, or 32 mg/L OTC. After an 18-20 hour incubation period, colonies that turned black were enumerated. By comparing the number of colonies grown on different plates, the antimicrobial resistance level of the internalized Salmonella was determined. Results show that the antibiotic resistance levels of Salmonella grown in LB media not receiving OTC, Salmonella internalized lettuce not receiving OTC, and Salmonella internalized in lettuce receiving OTC were all at 32 mg/L OTC. In addition, no significant differences were observed among different lettuce growth stages.

Mentor: Dr. Xu Li, Department of Civil Engineering

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Jason B. ThomasA Closer Look at the Assistant
(to the) Regional Manager:
Personality Differences Between
First and Second in Command
Leaders in Organizationshttp://digitalcommons.unl.edu/mcnairjournal/8
http://digitalcommons.unl.edu/mcnairjournal/8Thu, 04 Apr 2013 08:46:09 PDT
Although a great deal of research has established personality differences between leaders and their followers (Lord, de Vader, & Alliger, 1986) there has been little research on how leaders at different levels of organizations may differ from one another. In particular, no research to date has examined whether or not there are personality differences between those who are first in command of their organizations and those second in command. The present study attempts to explore whether or not these differences exist in terms of both lay perceptions and in reality. The researchers in this study asked 401 individuals to contrast the personalities of first- and second-in-command leaders in general. Results generally showed that lay individuals believed that first-in-command leaders were extraverted and open to new experiences while second-in-command leaders were more neurotic. Next, the researches verified whether or not these stereotypes were true by having 1,262 individuals rate their actual first- or second-in-command leaders. First-in-command leaders were rated as being higher on conscientiousness. Second-in-command leaders were rated as being higher on neuroticism. Although there were fewer significant differences between the two levels of leadership, the pattern of differences between these leadership roles was consistent with lay stereotypes for these roles. Though the differences were not substantial, there was a great deal of accuracy in perceiving the traits that were different.
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Ross BenesMicrobiologically Enhanced Mixing across Scales during <i>in-situ</i> Bioremediation of Uraniumhttp://digitalcommons.unl.edu/mcnairjournal/7
http://digitalcommons.unl.edu/mcnairjournal/7Thu, 13 Dec 2012 10:15:12 PST
Production of nuclear fuels for weapons and electric energy has resulted in groundwater uranium contamination at Department of Energy (DOE) sites. Reduction of uranium by dissimilatory metal-reducing bacteria (DMRB) is an effective approach for in-situ bioremediation of these sites. In this process, an organic electron donor is typically delivered through a well into groundwater in order to promote the biological reduction of soluble and toxic U(VI) to insoluble and less toxic U(IV). A key challenge is mixing the organic electron donor with U(VI) in groundwater where laminar flow conditions prevail. A potential solution is to enhance reaction beyond the scale of physical mixing by promoting extracellular electron shuttling. Growing evidence suggests that extracellular electron shuttling can occur by either diffusion of aqueous phase electron shuttles (e.g., H2, quinones) between syntrophs and/or DMRB, or through direct electron transfer between cells through metallic-like appendage (i.e., nanowires). In this project, we used pore scale, microfluidic experiments in order to elucidate cell-to-cell electron transport that can potentially enhance U(VI) reduction beyond the scale of physical mixing with an organic electron donor. Batch studies were performed to develop DMRB cultures, and to evaluate their growth with different electron acceptor and donor conditions. DMRB cultures from batch studies were used to inoculate pore scale, microfluidic reactors. The microfluidic experiments allowed direct imaging of microbial growth over various mixing length scales. Anaeromyxobacter dehalogenans Strain K and a mixed ground water culture were used, and we hypothesize that these organisms will enhance reaction beyond physical mixing scales by facilitated electron transfer.
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Reinaldo E. AlcaldeDebt Relief or Debt Cycle: A Secondary Analysis of the Heavily Indebted Poor Countries (HIPC) Initiative in African Nationshttp://digitalcommons.unl.edu/mcnairjournal/6
http://digitalcommons.unl.edu/mcnairjournal/6Mon, 28 Nov 2011 14:16:25 PST
In 1996, the International Monetary Fund (IMF) and World Bank launched the Heavily Indebted Poor Countries (HIPC) Initiative. The HIPC Initiative is a comprehensive approach to debt reduction designed to ensure that no poor country faces a debt burden it cannot manage (International Monetary Fund, 2011). To date, debt reduction packages providing US $72 billion under the HIPC Initiative have been approved for 36 countries, 32 of them in Africa (International Monetary Fund, 2011). Under the HIPC Initiative, the World Bank and IMF Boards first decide whether or not a country is eligible for debt relief (decision point document). In a second step, all creditors (multilateral, bilateral, and commercial) commit debt relief to be delivered at a “floating” completion point. In between those steps, the country tries to implement the policies determined at the decision point (which are triggers to reaching the completion point). This research paper will examine the HIPC Initiative using a secondary analysis to determine the effectiveness of this program for indebted countries in Africa. The results of this analysis are anticipated to assist in determining weaknesses in debt relief programs, such as the HIPC Initiative, as well as indicate historical economic conditions that set contemporary cycles of debt in motion in Africa.
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Misam B. AliRelationship of Obsessive-Compulsive Behaviors of Primary Caregivers with a History of Sexual Abuse and Perfectionism in their Sexually Abused Childrenhttp://digitalcommons.unl.edu/mcnairjournal/5
http://digitalcommons.unl.edu/mcnairjournal/5Wed, 09 Nov 2011 10:25:59 PST
Childhood sexual abuse (CSA) is associated with many short- and long-term sequelae including obsessive-compulsive behaviors (OCB) and perfectionism. Research suggests that the expression of child perfectionism may be influenced by caregivers’ OCB and CSA history. Caregivers with a CSA history may engage in dysfunctional parenting styles associated with child perfectionism, while children of caregivers with OCB may exhibit increased perfectionism due to genetics and/or the internalization of their parents’ perfectionist tendencies. However, given the high prevalence of OCB among those with a CSA history, the relationships among caregivers’ expression of OCB, caregivers’ CSA history, and child perfectionism is unclear. Thus, the purpose of this study was to explore these relationships. Results indicated that, consistent with existing literature, caregivers with a CSA history had significantly greater OCB than caregivers without a CSA history. However, caregiver OCB was not associated with perfectionism in youth who experienced CSA. Alternatively, children whose caregivers had a history of CSA exhibited significantly greater perfectionism than children of caregivers without a CSA history. Moreover, regression analyses revealed that caregiver CSA history significantly contributed to a model predicting child perfectionism.
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Alyssa Lundahl et al.Factors Associated with Participation and Retention in a Group Treatment for Child Sexual Abusehttp://digitalcommons.unl.edu/mcnairjournal/4
http://digitalcommons.unl.edu/mcnairjournal/4Wed, 09 Nov 2011 09:38:39 PST
The current study examines factors associated with participation and retention in a child sexual abuse (CSA) outpatient program. Participation and retention are vital if children are to receive the intended benefits of treatment designed to promote healthy coping following CSA. However, little is known about factors that impede or encourage families to consistently attend sessions. Several factors possibly related to child participation and retention were examined, including demographic variables such as income level and education, characteristics of the abuse, and parent and family pretreatment functioning. Participants in the sample included 175 children and adolescents and their non-offending primary caregivers seeking cognitive-behavioral group treatment at an outpatient clinic following disclosure of CSA by the participating child. Pretreatment assessment data and records of treatment attendance, gathered as part of a larger research endeavor evaluating the effectiveness of the treatment protocol, were utilized. The results indicated that demographic variables reflective of reduced structural barriers to treatment seeking (e.g., higher income) have a positive effect on participation and retention. Results did not indicate a relationship between abuse characteristics and participation and retention. Finally, mixed results regarding parent and family functioning emerged. While significant relationships were not found across all measures; several analyses indicated a positive relationship between parental functioning, family functioning, and participation and retention. Implications of the study’s results for clinicians who are aiming to engage families in treatment following CSA are presented. Informed about factors that promote retention and steady participation, clinicians will be able to identify and ameliorate difficulties that may lead to either inconsistent attendance or discontinued treatment.
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Mollie Dittmer et al.Examining Attitudes on Organ Donation for Transplant: Amenability to Financial Incentives and Donor Benefitshttp://digitalcommons.unl.edu/mcnairjournal/3
http://digitalcommons.unl.edu/mcnairjournal/3Tue, 14 Dec 2010 14:43:18 PST
The Uniform Anatomical Gift Act (UAGA) currently outlaws the sale of organs for transplant purposes, despite the technological advances since its inception in 1968 and the current disparity between the need for and availability of organs. Increasingly, research has been done to determine interest in and feasibility of financial incentives and donor benefits. The author of the current study developed a self-report survey gauging attitudes towards live and post-mortem donation in general, and towards potential alternatives to the organ donation system involving financial incentives and donor benefits. Students at a large Midwestern university were asked about their likelihood of use of alternative programs, as well as demographic questions, including gender, race/ethnicity, and prior experience with organ donation, in hopes of determining which populations are most amenable to alternatives. In bivariate analyses, the study found that gender had no bearing on likelihood of use for the current system or for alternative systems. Moreover, white non-Hispanics were more likely than other racial ethnic groups to donate in various incentive programs. Also, those without previous experience with organ or tissue donation were more likely than those with experience to donate if paid by the recipient for live organs. Finally, being registered as an organ donor was shown to increase likelihood of organ donation in various programs. Gender, previous experience, and registration status were used in three-way factorial designs and demonstrated interactions, indicating that the variables may require a higher-order effect to demonstrate demographic differences.

Mentor: Dr. Susan Jacobs, School of Criminology and Criminal Justice, University of Nebraska-Omaha
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Karise CarrilloInsight and Locus of Control as Related to Aggression in Individuals with Severe Mental Illness (SMI)http://digitalcommons.unl.edu/mcnairjournal/2
http://digitalcommons.unl.edu/mcnairjournal/2Wed, 25 Aug 2010 10:57:37 PDT
Individuals with severe mental illness (SMI) are often stereotyped as aggressive, although research has shown that the majority of these individuals are not aggressive. Nonetheless, closer examination of factors that differentiate high-aggressors from low-aggressors may predict which individuals are more likely to become verbally and/or physically aggressive. Previous studies have investigated the relationship between insight and aggression in this population. Some studies have found a relationship between poor insight and aggression, while others have not. Other studies have also examined the relationship between locus of control and aggression, and many have found that an external locus of control is related to higher aggression. The current study examined the relationship between insight, locus of control, and aggression in individuals with SMI. Forty-four participants with SMI were included. Participants were grouped according to history of aggressive behavior. A linear discriminant function analysis was performed. Neurocognitive functioning was forced into the discriminant equation to control for the possible effects of neurocognitive impairment on aggression, and the insight and locus of control variables were entered in a second block. The analysis did not identify a significant discriminant function. The insight and locus of control variables were unable to correctly reclassify a significant number of participants into their previously determined categories. In sum, insight and locus of control do not appear to be significantly related to aggression, and it is likely that there are a multitude of other variables that contribute to the occurrence of aggressive behaviors.
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Bethany L. RidlingChild Sexual Abuse Victims and their Families Receiving Services at a Child Advocacy Center: Mental Health and Support Needshttp://digitalcommons.unl.edu/mcnairjournal/1
http://digitalcommons.unl.edu/mcnairjournal/1Wed, 25 Aug 2010 10:56:02 PDT
The present study aimed to document the effects of child sexual abuse among children, non-offending parents, and siblings to further address the needs of child victims and their families. Following abuse, children are often referred to Child Advocacy Centers (CACs) for mental health and other support needs. Today most sexually abused children receive homogenized treatment from CACs; however, there is variability in the needs these children and their family members present with (Finkelhor & Berliner, 1995). Research has begun to investigate the variability in symptom patterns of sexual abuse victims, finding aspects of the abuse including severity, duration, frequency, and amount of force seem to affect the types of symptoms displayed by sexual abuse victims (Kendall-Tackett et al., 1993).

This exploratory study examined the nature of presenting needs of sexually abused youth and their families. Participants were child victims, their siblings, and their caregivers seeking treatment at a Midwestern CAC. Participants were given a battery of measures that assessed mental health, efficacy, expectations, knowledge and behaviors. As we hypothesized, there was heterogeneity in the mental health and support needs of child victims and family members. Varying expectations, levels of efficacy, and mental health states of child victims, siblings and parents seem to contribute to the need for different types of treatment and support for sexually abused children and their families. Based on these findings, it would be beneficial for CACs to incorporate programs to address the varied mental health and support needs of child sexual abuse victims and their families.
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Tara K. Cossel